Gov. Rick Scott and Republican lawmakers will propose changes to Florida gun laws Friday that will spark the most intense debate over guns in many years and could reshape the political landscape for the fall elections in the nation's largest swing state.

The proposed changes are the state's response to the mass shooting in Parkland last week, and Democrats say they don't go far enough.

The bills are expected to raise the age from 18 to 21 to buy semi-automatic weapons and high-capacity magazines; expand background checks, mental health and school safety; and give police more power to use the Baker Act to keep weapons away from people with mental health problems.

What won't be in any of the bills is a ban on the sale or possession of assault weapons, like the AR-15-style rifle used in the Parkland attack that killed 17 people last week.

Despite a long history of behavioral and mental health issues and threats of violence, confessed killer Nikolas Cruz, 19, legally bought his weapon a year ago.

All 15 Senate Democrats want an assault weapons ban. They will propose it Monday at a Senate Rules Committee meeting when three gun bills are debated for the first time: SB 7022, SB 7024 and SB 7026.

"So long as assault rifles like the AR-15 are legally sold in this state, so long as they are not banned, their threat to civilians will remain in every school, every mall, every movie theater, every nightclub, and in every place the public gathers," said Senate Democratic Leader Oscar Braynon, D-Miami Gardens.

Democrats in both houses filed bills to ban assault weapons after the Pulse nightclub attack in 2016 but they were not heard, even as several pro-gun bills moved forward — before the massacre at Marjory Stoneman Douglas High School.

In August and October of last year, the same bills (SB 196 and HB 219) were filed again for this session, but were not heard. In Tallahassee, Republicans alone decide which bills are considered, and the proposed bans were ignored.

House Democrats tried to procedurally dislodge HB 219 from a frozen committee stop Tuesday to debate it, but Republicans refused.

The roll call vote sheet, showing 71 Republicans voting no, lit up social media, and Democrats portrayed it as a vote against a ban on assault weapons. One Republican called that move a "stunt" Thursday.

Rep. Randy Fine of Brevard County, asked by CNN if the House will debate an assault weapons ban, replied: "We're going to have a debate on a comprehensive bill and as that bill moves through the process, any member can make any amendment they want to that bill that is germane, and it will be discussed and voted on by the membership."

Fine added: "I'm not a big fan of taking away folks' Second Amendment rights. I think we need to look at the issues and see where we can play around the edges, but we have to remember that people have the right to keep and bear arms, and there are tens of millions of gun owners who act responsibly every day. "

Republicans hold a 76-41 advantage in the Florida House with three seats currently vacant.

Democrats realize they don't have enough votes to win on an assault weapons ban, but that's beside the point. Republicans say Democrats are using an assault weapons ban to fire up the party's liberal anti-gun base.

In an election year, Democrats want to put Republicans on record as opposing a ban on sales of assault weapons, believing it can change the outcome of elections in a year that already appeared very uncertain for Republicans.

Another Republican who voted to block debate on an assault weapons ban, Rep. Gayle Harrell of Stuart, said Thursday: "Now is the time for thoughtful consideration of positive solutions, not politically motivated manipulation of the situation."

House Speaker Richard Corcoran, R-Land O'Lakes, who like many other GOP legislators enjoys an A rating from the National Rifle Association, defended the decision to block debate on assault weapons.

"Rules matter. That's what makes our country great," Corcoran said. "You have to follow the rules."

Corcoran said bills are not supposed to be withdrawn from committees, but Republicans have refused to scheduled the issue for debate in committees. Bills should only reach the floor of the House after "the public has had plenty of input," Corcoran said.

The partisan skirmishes are a clear sign that with two weeks left in the regular session, the debate over assault weapons is far from over. Democratic Rep. Kionne McGhee of Miami said Florida needs to consider a minimum 20-year moratorium on assault weapons. He dismissed talk of a political agenda in support of a ban.

"I don't think any political party should be looking at this as a way to politicize or pick up seats," McGhee said. "We have an opportunity that we haven't had in 20 years to bring about change as it relates to guns. If we can't get a ban, at least give us a 20-year moratorium."

Democratic Rep. Jared Moskowitz of Coral Springs said: "At some point in time, we'll be debating a complete ban."

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